On the "Details" page of your test results, click on any of your static resources, then on "Response" to see the cache headers returned. My guess is that you haven't set up these headers for your static resources. If you can also allow caching of your dynamic content, that could lower your TTFB significantly; currently, CloudFlare probably has to fetch the document from your server before it can serve it to the client, introducing more latency than if you were to serve it directly from your server.